TOKYO – There is no doubt North Korea violated United Nations Security Council resolutions by testing ballistic missiles this month, national security adviser John Bolton said on Saturday, adding that President Donald Trump is determined to maintain sanctions pressure on the regime until it backs down.

The comments mark the first time a senior administration official has confirmed that North Korea launched ballistic missiles in contravention of U.N. resolutions, with officials appearing reluctant until now to make such a clear statement to demonstrate their willingness to restart dialogue.

But in a tweet just after 7:30 a.m. Sunday local time, Trump directly contradicted his national security adviser, writing, “North Korea fired off some small weapons, which disturbed some of my people, and others, but not me.”

“I have confidence that Chairman Kim will keep his promise to me,” Trump added.

Bolton and Trump have disagreed on a number of issues in recent weeks, including just how hawkish a stance to take in conflicts with Venezuela and Iran, and that friction has recently spilled into public view. Earlier this month, Trump praised Bolton to reporters but noted that he and his national security adviser often have different views about the use of American power and foreign intervention.

In his tweet, Trump also misspelled former vice president Joe Biden’s name, and seemed to side with North Korea and its leader Kim Jong Un over Biden – a Democratic presidential candidate, on whom Trump and his allies are most focused – saying he had appreciated a recent comment by North Korean state media calling Biden a “low IQ idiot” whose candidacy should not carry high expectations.

Trump wrote that he “also smiled when he called Swampman Joe Bidan a low IQ individual, & worse. Perhaps that’s sending me a signal?”

With Trump in Tokyo for a state visit, he faces deadlock and the possible collapse of what he considers to be one of his key foreign policy achievements, calming tensions with Pyongyang, ending its nuclear and missile tests and starting a dialogue about denuclearization.

But missiles are being tested, talks have completely dried up and threatening language is on the rise, with both sides demanding that the other back down, in what amounts to a nuclear-armed staring match.

North Korea conducted two sets of missile tests earlier this month, with Bolton describing them as “close-range ballistic missiles,” as well as “more standard SRBMs, short-range ballistic missiles.” U.N. Security Council resolutions, including Resolution 1695, specifically prohibits North Korea from launching any ballistic missiles, he said, adding: “I know that because I wrote it.”

“In terms of violating Security Council resolutions, there’s no doubt about that,” Bolton told reporters on Saturday, hours before Trump was due to land and be greeted by Japanese Prime Minister Shinzo Abe.

“I think the prime minister and the president are going to talk about making sure the integrity of the U.N. Security Council resolutions is maintained,” he said.

On Friday, North Korea’s foreign ministry again blamed the United States for deliberately causing the collapse of the Hanoi summit between Trump and Kim Jong Un by making unilateral and impossible demands.

Dialogue between the two countries will never be resumed unless the United States changes its “calculation,” an unnamed foreign ministry spokesman told the Korean Central News Agency, “and the further its mistrust and hostile acts toward the DPRK grow, the fiercer our reaction will be.”

North Korea’s formal name is the Democratic People’s Republic of Korea.

“God knows what they said this time,” Bolton said when asked about the latest comments. “After many years of being called human scum by North Korea, I take most of what they say with a grain of salt.”

But he made it clear the Trump administration was not about to change its stance.

“The North Korean leadership well knows the president’s view,” he said, which he said concurs with that of Abe: “keeping sanctions in place and in force until North Korea shows it has made a strategic decision to give up its nuclear weapons.”

“I don’t think that’s going to change,” he added.

Bolton rejected suggestions he was behind a hardening of the U.S. negotiating position in Hanoi, arguing it had been Trump’s consistent position, dating back to the campaign trail as well as last year’s Singapore summit with Kim, that North Korea can have a bright future if it surrenders its nuclear arsenal.

“The president’s opened the door to North Korea, and we’re just waiting for them to walk through it,” he said.

Bolton said Stephen Biegun, the U.S. special representative for North Korea, “can’t wait” to meet his North Korean counterpart again, “but they haven’t responded,” adding that Biegun was ready to get on a plane and go “anywhere, any time.”

“We really haven’t heard much from the North Koreans since the Hanoi summit, nor has President Moon of South Korea,” he said.

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